false

1988

The living freshwater gastropod Melanopsis dufouri (FERUSSAC) has two morphotypes. The study of chemical variation of trace-elements in this gastropod and its correlation with the environmental fluctuation are the aim of this paper. Due to the genus Melanopsis has an abundant fossil record during the Cenozoic, the results of the present work could be of paleoecological interest. Trace-elements are embodied in the shell during growth. The shell of M. dufouri has accretionary growth. There are several examples cited on circadian accretionary growth in invertebrate shells. However, in the present case and as a first conclusion, the accretion rate depends on the size of the shell. In a short-ti…

Partial purification and initial characterization of phytochrome from the mossAtrichum undulatum P. Beauv. grown in the light.

1988

The extraction and partial purification of phytochrome from light-grownAtrichum undulatum P. Beauv., a chlorophyllous moss, is described. Polyethyleneimine and salt fractionation followed by hydroxyapatite and Affi-gel-blue chromatography were used to separate phytochrome from chlorophyll, and to purify the pigment. All steps were performed in the presence of Triton X-100 which improved the yield by a factor of about three. The protein has a molecular weight some-what larger than that ofAvena phytochrome (124 kDa), as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblot analysis. It cross-reacts with a monoclonal antibody against phytochrome from etiolated …

ChemInform Abstract: A Simple and General Synthesis of Symmetrical and Unsymmetrical Bis(arylamino)methanes. Reactions of N,O-Acetals with Nitrogen B…

1988

Bis(arylamino)methanes 4 free of amine contamination have been efficiently synthesized from N,O-acetals 1 following three different methodologies. The first two are useful for symmetrical aminals and involve the decomposition of an N,O-acetal by a base (phenyllithium or a lithium arylamide) and trapping of the resulting methyleneamine 2 by the equimolar amount of the corresponding arylamine. The third method allows the preparation of either symmetrical or unsymmetrical aminals and consists of decomposing the starting N,O-acetal 1 by heating in vacuo in the presence of the desired arylamine. Ein einfacher und allgemeiner Zugang zu symmetrischen und unsymmetrischen Bis(arylamino)methanen. Rea…

Laminar distribution and morphology of gamma-aminobutyric acid (GABA)-immunoreactive neurons in the medial and dorsomedial areas of the cerebral cort…

1988

The morphology and laminar distribution of immunolabeled neurons in the medial and dorsomedial telencephalic cortices of the lizard Podarcis hispanica were examined in vibratome sections after preembedding γ-aminobutyric acid (GABA)-immunocytochemistry. In both cortical areas and at all rostrocaudal levels, GABA-immunoreactive neurons were found in all cortical layers, with the largest number (74%) of GABA-positive cells in layer 3. GABA-positive neurons were classified into pyramidlike, vertical-fusiform, multipolar, and horizontal neurons. Cells that could be so classified were counted in each cortical lamina. In the medial cortex, multipolar and horizontal-bipolar cells dominated layer 1…

Monohydroxylated fatty acid substrate specificity of human leukocyte 5-lipoxygenase and ω-hydroxylase

1988

Various monohydroxylated fatty acids were synthesized from eicosapolyenoic acids, namely arachidonic (20:4 omega-6), timnodonic (20:5 omega-3), dihomogammalinolenic (20:3 omega-6) and mead (20:3 omega-9) acids. 12-Hydroxy derivatives, as well as 12-hydroxy-5,8,10-heptadecatrienoic acid (HHT), were produced with platelets as the enzyme source, and 15-hydroxy derivatives were produced by soya bean lipoxygenase treatment. Each monohydroxylated fatty acid was incubated with human leukocytes in the presence or absence of the calcium ionophore A23187, and dihydroxylated products were analysed by h.p.l.c. 12-Hydroxy derivatives of 20:4 omega-6, 20:5 omega-3 and 20:3 omega-9 were similarly oxygenat…

Der Phenylacetyl-(PhAc-)Rest als enzymatisch ablösbare Schutzgruppe für Peptide und Kohlenhydrate: Selektive Schutzgruppenabspaltungen mit Penicillin…

1988

N-Phenylacetyl-(PhAc-)-aminosauren werden mit Aminosauremethyl-, -benzyl-, -allyl- und -tert-butylestern mit Hilfe des modifizierten Carbodiimidverfahrens oder unter Verwendung von EEDQ in guten Ausbeuten zu vollgeschutzten Dipeptiden verknupft. Der PhAc-Rest ist bei den Abspaltungen der C-terminalen Schutzgruppen stabil, kann jedoch aus den Peptiden unter nahezu neutralen Bedingungen selektiv mit Penicillin-Acylase (EC 3.5.1.11) abgelost werden. Das Enzym hydrolysiert den PhAc-Rest auch aus der 2-Position von acetylgeschutzter Glucose, der 3-Position von Di-O-isopropylidenglucose und der primaren OH-Gruppe von Di-O-isopropyliden-L-sorbose. Bei den enzymatischen Abspaltungsreaktionen bleibe…

The Allyl Ester as Carboxy-Protecting Group in the Stereoselective Construction of Neuraminic-Acid Glycosides

1988

The application of the allyl-ester moiety as protecting principle for the carboxy group of N-acetylneuraminic acid is described. Peracetylated allyl neuraminate 2 is synthesized by reacting the caesium salt of the acid 1 with allyl bromide. Treatment of 2 with HCl in AcCl or with HF/pyridine gives the corresponding 2-chloro or 2-fluoro derivatives 3 and 4, respectively (Scheme 1). In the presence of Ag2CO3, the 2-chloro carbohydrate 3 reacts with di-O-isopropylidene-protected galactose 5 to give the 2–6 linked disaccharide with the α-D-anomer 6a predominating (α-D/β-D = 6:1; Scheme 2). Upon activation of the 2-fluoro derivative 4 with BF3 · Et2O, the β-D-anomer 6b is formed preferentially (…

Foreign Aid to Education in Sub-Saharan Africa : How Useful Is It?

1988

International audience

Family studies in scleroderma (systemic sclerosis) demonstrating an HLA-linked increased chromosomal breakage rate in cultured lymphocytes

1988

An increased chromosomal breakage rate (ICBR) was found in 27 of 28 patients with scleroderma (systemic sclerosis, SS) - 5 with the syndrome including calcinosis cutis, Raynaud phenomenon, esophagus hypomotility, sclerodactyly and telangiectasia (CREST), 4 incomplete CREST, 1 overlapping syndrome, 18 progressive systemic sclerosis (PSS). Not only the patients, but also about half of their first-degree relatives showed an increased chromosomal breakage rate (more than 5 breaks per 100 metaphases). This character segregated as a dominant marker in nine families of scleroderma patients. In the six informative of the nine families, the ICBR trait showed close linkage with the HLA region on chro…

Comparison of enzyme phenotypes in human bladder tumours and experimentally induced hyperplastic and neoplastic lesions of the rat urinary bladder. A…

1988

The expression of a number of enzymes involved in drug metabolism, membrane function etc. was compared in hyperplastic and neoplastic lesions of the rat bladder and in human bladder tumours. Transitional cell carcinomas (TCC) in both rat and Man were characterized by decreased alkaline phosphatase (ALP) and increased gamma-glutamyl transpeptidase (GGT), beta-glucuronidase (beta-G1), succinate dehydrogenase (SD) and glucose-6-phosphate dehydrogenase (G6PD) activities. In addition, binding for antibodies specific for different cytochrome P-450 species (UT50, PB3a, MC1, MC2) and microsomal epoxide hydrolase (mEHb) was elevated in both murine and human tumours. Comparison of the enzyme phenotyp…

Thermodynamics of transfer of some nitroalkanes from aqueous to dodecyltrimethylammonium bromide micellar phases

1988

Abstract The enthalpies of mixing of some aqueous n-nitroalkane solutions with dodecyltrimethylammonium bromide micellar solutions were determined. The experimental data were treated by using a previously reported approach giving the enthalpies of transfer of solute from the aqueous to the micellar phases and the distribution constant of solute between the two phases at the same time. From these, the standard thermodynamic quantities of transfer (ΔtrfG°, ΔtrfH° and ΔtrfS°) are derived. In order to study the effect of the nature of both the solvent and the head group of solute, these properties are compared with those from water to octane and with those of alcohols and nitriles from aqueous …

Daily hormonal and neuromuscular responses to intensive strength training in 1 week.

1988

Daily adaptive responses in the neuromuscular and endocrine systems to a 1-week very intensive strength training period with two training sessions per day were investigated in eight elite weight lifters. The morning and the afternoon sessions resulted in acute decreases (P less than 0.05-0.01) in maximal isometric strength and in the maximal neural activation (iEMG) of the leg extensor muscles, but the basic levels remained unaltered during the entire training period. Significant (P less than 0.05-0.01) acute increases in serum total and free testosterone levels were found during the afternoon sessions. During the 1-week training period, serum total and free testosterone concentrations decr…

Glutathione Peroxidase Activity and Selenium Therapy in Muscular Dystrophies

1988

HSV hepatitis in the mouse: A light and electron microscopic study with immunohistology and in situ hybridization

1988

In order to characterize better the morphology and immune response in acute necrotizing HSV infection, murine HSV hepatitis was examined. BALB/c mice were inoculated intraperitoneally with 10(6) plaque-forming units (PFU) of HSV-1 (Lenette) and HSV-2 (D316). In both groups half the animals were pretreated with silica particles to block macrophage function. Up to 6 days after infection four mice from each group were sacrificed at daily intervals and the livers were examined by light and electron microscopy, immunohistology, in situ hybridization, combined immunohistology/in situ hybridization and titration of viral PFU. HSV-2 infected mice developed severe necrotizing hepatitis with persiste…

Biindenyls, Biindenylides, and Diindeno‐Fused Heterocycles from Oxidative Coupling of 1‐ and 2‐Indanone

1988

1- and 2-indanone are transformed into the corresponding enolates and oxidatively coupled to yield 1,4-diketones providing easy access to a series of biindenyls, diindeno-fused heterocycles, and biindenylides. Biindenyle, Biindenylide und Diindeno-kondensierte Heterocyclen durch oxidative Kupplung von 1- und 2-Indanon 1- und 2-Indanon werden in die Enolate ubergefuhrt und oxidativ zu 1,4-Diketonen gekuppelt. Diese bieten einen einfachen Zugang zu einer Reiher von Biindenylen, Diindeno-kondensierten Heterocyclen und Biindenyliden.

Strukturaufklärung mit moderner NMR-Spektroskopie. Ein Übungsbuch. Von H . Duddeck und W. Dietrich. Steinkopff Verlag, Darmstadt 1988. 197 s., paperb…

1988

The Study of Prompt and Delayed Muon Induced Fission; II. Mean life times of negative muons bound to 237Np, 242Pu and 244Pu

1988

The mean life times of negative muons bound to actinide nuclei have been measured by detecting the time difference between a stopped muon and the arrival of fragments from delayed fission after muon capture. The deduced capture rates c are 1.392(4)·107/s for237Np, 1.290(7)·107/s for242Pu and 1.240(7)·107/s for244Pu. The results are compared with published data for the fission and the neutron decay channels and for the electron decay of the bound muon. Including a former measurement of c for239Pu, an isotopic dependence of the muon capture rates in the Pu isotopes is clearly observed.

Nucleation and accretion of bioelastomeric fibers at biological temperatures and low concentrations.

1988

Quasi-elastic light scattering (QELS) studies are reported, which address the early stages of aggregation of the polypentamer poly(VPGVG). This reflects the major primary structural feature of native elastin. The study is focused on the region of the phase diagram which in both its temperature and concentration range is closest to the state of affairs occurring in the course of bioelastogenesis by progressive synthesis of the precursor protein. Results here reported allow for the first time a self-consistent view of the physics of elastogenesis, and specify the role of the region of metastability and of that of instability of the phase diagram in the non-chaotic, orderly formation of elasto…

Neuromuscular and hormonal adaptations in athletes to strength training in two years.

1988

Neuromuscular and hormonal adaptations to prolonged strength training were investigated in nine elite weight lifters. The average increases occurred over the 2-yr follow-up period in the maximal neural activation (integrated electromyogram, IEMG; 4.2%, P = NS), maximal isometric leg-extension force (4.9%, P = NS), averaged concentric power index (4.1%, P = NS), total weight-lifting result (2.8%, P less than 0.05), and total mean fiber area (5.9%, P = NS) of the vastus lateralis muscle, respectively. The training period resulted in increases in the concentrations of serum testosterone from 19.8 +/- 5.3 to 25.1 +/- 5.2 nmol/l (P less than 0.05), luteinizing hormone (LH) from 8.6 +/- 0.8 to 9…

Clinical results of transanal endoscopic microsurgery

1988

Using the "transanal endoscopic microsurgery" technique, 140 patients were treated at the Department of Surgery in Cologne and Mainz. Of the patients with adenomas, 68.2% had typical symptoms preoperatively. The postoperative hospital attendance was 8.7 days, with an average resection size of 14.4 cm2. The postoperative complication rate was 5%, and there were no deaths related to the technique. In a prospective controlled trial, 2.2% of the patients with adenomas treated endoscopically in Mainz showed recidivation, requiring reoperation. The follow-up rate was 100%. In 30 cases, microscopic examination revealed carcinoma. Radical reoperation in 8 pT1 tumours showed neither remaining tumour…

Higgs-boson radiative corrections to the decayS13(QQ¯)→Hγ

1988

We consider one-loop radiative corrections to the Wilczek mechanism (/sup 3/S/sub 1/(QQ-bar)..-->..H..gamma..) due to a subset of the electroweak theory, the Higgs sector, in the standard model and discuss extensions to two-Higgs-doublet models. We discuss the circumstances under which such corrections can be important.

Electron Transfer and Conformational Interconversions in 1, n ‐Diphenylpolyenes

1988

1,4-Diphenylbutadiene (1), 1,6-diphenylhexatriene (2), and 1,8-diphenylocatatetraene (3) are reduced with alkali metals and the resulting paramagnetic monoanions and diamagnetic dianions characterized by ESR and (1H-, 13C-)NMR spectroscopy, respectively. The stereodynamic behavior of the ions is studied as a function of chain length, charge, and counterion. The reduction of 1, 2, and 3 serves as a model experiment for the doping of extended linear polyenes (polyacetylenes). Elektronenubertragungen und Konformationsanderungen in 1,n-Diphenylpolyenen 1,4-Diphenylbutadien (1), 1,6-Diphenylhexatrien (2) und 1,8-Diphenyloctatetraen (3) werden mit Alkalimetallen reduziert, und die resultierenden …

Gender-Differences in Sport and Movement in Finland

1988

Male and female age-cohorts resemble each other quite clearly in their sport involvement. The greatest differences between men and women are shown to be in organized and competitive sports mainly practiced by men, and in so-called "untied" movement (i.e. physical exercise that does not require any pre-arrangements), more of a female domain. The various age-cohorts differ in sport involvement from each other more among men than among women. This is examined from several angles: as a question of role or gender expectations, of different life-situations and possibilities, of different meanings and contents of sport and movement, and of different sport cultures and myths.

Regularity and polar sets for supersolutions of certain degenerate elliptic equations

1988

On considere l'equation ⊇•⊇ h F(x,⊇u(x))=0. Cette equation est non lineaire et degeneree avec des coefficients mesurables. On etudie la regularite des supersolutions

Changing female spacing behaviour and demography in an enclosed breeding population of Clethrionomys glareolus

1988

The social organization of Clethrionomys glareolus Schreber was studied by live trapping in an enclosure of 0.8 ha in Central Finland between the years 1982–1986. The enclosure consisted of three habitats: abandoned field, brushwood, and moist spruce heath forest. The population density increased from 50 voles ha−1 in 1982 and 1983 to 150 ha−1 in 1984 and 1985. In the summer of 1986 the population crashed to almost zero. In the summer of 1984 after winter breeding the number of breeding females grew to 22 compared with 6–7 in previous years. In 1984 the mature females changed from territorial to group behaviour. During the high population density in 1984 and 1985 breeding stopped already in…

On the classification of observations structured into groups

1988

The paper is concerned with the problem of classifying a specific group into two populations (insect eggs of the same clutch belonging therefore to the same species). Two approaches, one parametric and the other non-parametric, are described. The classical likelihood ratio procedure is derived. An interpretation and a decomposition of the test criteria is given. A misclassification estimate using the Chernoff–Kullback–Kailath region is provided.

Pharmacological analysis of intrinsic neural control of rat duodenum motility in vitro

1988

Orthometallation reactions of rhodium compounds containing orthohaloarylphosphines

1988

The reaction of RhCl3·.3H2O with a 3-molar proportion of P(o-ClC6H4)Ph2, (PCCl) at room temperature gives RhCl(PCCl)2 (1), in high yield. Reaction of [Rh(cot)2Cl]2, (cot = cyclooctene), with PCCl, sol12 molar ratio, also gives compound 1. Refluxing of a solution of 1 in 96% ethanol gives RhCl2(PC)(η2-PCCl), [PC  (C6H4)PPh2] (2). Complex 1 reacts with CO to give RhClCO(PCCl)2 (3). 31P NMR studies reveal that 1 exhibits a fluxional behaviour in solution in the temperature range −50 to 0 °C. The low temperature spectrum is consistent with the formulation RhCl(η2-PCCl)(η1-PCCl). In cyclic voltammetry complex 2 shows two two-electronic reduction processes, at −0.98 and −1.56 V. Electrochemical …

Hyperfine structure and isotope shift of the neutron-rich barium isotopes139?146Ba and148Ba

1988

The hyperfme structure and isotope shift in the 6s 2 S 1/2−6p 2P3/2 line of Ba II (455.4 nm) have been measured by collinear fast-beam laser spectroscopy for the neutron-rich isotopes139–146Ba and148Ba. Nuclear moments and mean square charge radii of these isotopes have been recalculated. The isotope shift of the isotope148Ba (T1/2=0.64 s) could be studied for the first time, yieldingδ〈r2〉138,148=1.245(3) fm2.

Constraints on r-process conditions from beta-decay properties far off stability and r-abundances.

1988

The measured beta -decay properties of the 'waiting-point' nuclei 130Cd and 80Zn, together with improved shell model predictions of T1/2 and Pn-values for their experimentally unknown N approximately=82 and 50 neighbours, can be directly related to the observed r-abundances in the A approximately=130 and 80 abundance peaks. Based on this result, new constraints are given on the stellar conditions under which the r-process has operated.

New high-performance liquid chromatography-based methodology for monitoring the conformational transitions of self-associating hydrophobic peptides, …

1988

A new high-performance size-exclusion chromatographic strategy is reported for the analysis of the hydrophobic self-associating peptide gramicidin A, incorporated into artificial phospholipid vesicles (liposomes). The method is based on the direct injection of a few microlitres of the gramicidin A-containing liposome suspension into the column, which is eluted with a non-polar solvent, such as tetrahydrofuran. The type and amount of information which can be derived from this methodology have been evaluated. Using this chromatographic approach, a correlation has been unambiguously shown to exist between the organization of the peptide in the vesicles and a number of variables involved in the…

The generalized André systemsA(F,ß,(gi), (f i), ε)

1988

Incorporación de elementos traza en conchas de melanopsis durante el crecimiento : posibilidades de aplicación en paleoecología

1988

El objetivo del presente trabajo está encaminado al estudio de las variaciones de oligoelementos en la concha de un gasterópodo de agua dulce del género Melanopsis (U dufouri (FERUSSAC), con dos morfotipos) y si éstas tienen que ver, o no, con la fluctuación de una serie de parámetros ambientales. La importancia del trabajo radica en la posibilidad de la aplicación paleoecológica de sus resultados, ya que el género MelanopsÍs tiene un abundante registro fósil durante todo el Cenozoico. La incorporación de oligoelementos se efectúa a medida que la concha va creciendo por acreción; lo ideal sería que tal crecimiento fuera circadiano, ya que se podría seguir día a día, sobre la concha, la fluc…

Alpha-adrenergic modulation of glutathione metabolism in isolated rat hepatocytes.

1988

Glutathione metabolism was studied in isolated hepatocytes from 48-h starved rats. Phenylephrine (10 microM, final concentration) was incubated in the presence of a mixture of L-glutamine, glycine, L-serine, and L-methionine (at 10 times their normal plasma concentration). Alpha-adrenergic stimulation provoked a decrease in glutathione (GSH) synthesis. This effect was accompanied by an enhanced efflux of glutathione from the cells. Phenylephrine stimulated the rate of glutathione disulfide (GSSG) formation; however, this effect was clearly insufficient to explain the disappearance of GSH. Our results suggest that the decrease in cellular GSH levels observed under conditions of shock, stress…

Transduction of redox Gibbs free energy into modulated electrochemical work

1988

Abstract This work supplies an electrochemical model in order to account for some oscillatory phenomena. The model can be applied both to living bodies and to electrochemical cells. We suppose that one of the products of an electrochemical reaction in solution has a high vapour pressure and study the influence of its mass transfers on its oscillations and on that of the current,induced by the former ones. Mass transfers that we consider are either that from the solution to theatmosphere above it or both that due to bubble nucleation and that from the solution to the bubbles alreadynucleated. Two different oscillation conditions are determined. One derives from the resistance due to theinter…

Long-term effects of commercial and congeneric polychlorinated biphenyls on ethane production and malondialdehyde levels, indicators of in vivo lipid…

1988

Ethane exhalation was increased in male Sprague-Dawley rats following a single intraperitoneal (IP) injection of Aroclor 1254 (500 mg/kg). In the first 2 weeks following Aroclor 1254 treatment, the increase in ethane exhalation was due to an inhibition of metabolism of endogenous ethane rather than to an increase in ethane production. In weeks 3 and 4 following Aroclor 1254 administration, metabolic clearance of ethane returned to and exceeded control levels, while ethane production increased to approximately twice the control rates (day 30). The HPLC determination of in situ hepatic malondialdehyde levels revealed a 2-fold increase in malondialdehyde content on day 30 following the Aroclor…